The present invention refers to an insert holder of the blade type intended foremost for different turning applications, such as grooving, face grooving and parting. Slitting cutters and circular saw blades are also included in the term "blade type" insert holder.
Cutting inserts for grooving and parting are clamped in holders of the blade type, in order to allow narrow widths of cut. Such blade holders are normally made of steel, for example tool steel, and feature a number of different clamping arrangements for the actual cutting inserts. The inserts are made of hard material, generally cemented carbide. Different examples of various designs of clamping systems for cutting inserts in blade holders are referred to in U.S. Pat. Nos. 4,801,224; 4,588,333; 4,195,956; and EP-A-259 847. The cutting inserts are clamped in the free end of the blade holder, while the blade holder itself forms a part of a tool which even includes a tool shank that extends across the blade. The actual blade part can either be an integral part of the shank, or the blade part can be clamped in the shank portion by, for example, a screw or wedge-coupling, see for example Hedlund U.S. Pat. No. 5,688,080.
Common for all blade holders, irrespective of the design of the clamping system for the cutting insert, is that they can begin to vibrate, which naturally is a clear drawback. The vibration leads, for example, to poorer surface finish on the workpiece, damage to the cutting insert and even tool failure may occur.
Another problem with a large number of blade holders, in particular with narrow width and/or long overhangs, is an outward bending, or deflection of the blade part because of axial and tangential cutting forces.
The purpose of the present invention is consequently to diminish the tendency to vibration in holders of the blade type.
An additional purpose with the present invention is to reduce, as far as possible, all manner of bending of the blade part.